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14 Volt cockpit light

R

rk2436

Active Member
I've never been happy with the swivel light output. Know I know why ,it's only receiving 5vdc. The light is rated for 14vdc. Anybody rewire to 14vdc?
I'm thinking a quick fix would be to remove the seat pan and reroute the light feed to the cigarette outlet,yeah it would be on all the time but better than swapping pins in a db connector somewhere. Any thoughts?.
 
The cockpit light is already connected to positive 12 volts. The brightness is controlled by the negative side of the circuit. Later RV-12s have a brightness control POT (Potentiometer). In earlier RV-12s, the brightness is controlled via the Dynon. If the LED is rated for 14 volts and full brightness is desired, then the negative wire could be removed from the LED and replaced with a locally grounded wire. However, it might be too bright for night flying.
 
Mich48041 said:
The cockpit light is already connected to positive 12 volts. The brightness is controlled by the negative side of the circuit. Later RV-12s have a brightness control POT (Potentiometer). In earlier RV-12s, the brightness is controlled via the Dynon. If the LED is rated for 14 volts and full brightness is desired, then the negative wire could be removed from the LED and replaced with a locally grounded wire. However, it might be too bright for night flying.
Click to expand...

simply wire a potentiometer mounted in the on the floor covering in front of the flatiron handle and wire the ground side to local ground...
 
Th Brightness of the cockpit lighting is controlled by a PWM (pulse width modulation) circuit. When measuring the output voltage with a DC meter you are measuring the RMS value which will not be the same as the peak voltage value.
 
It flies so nice anytime of the day works for me. When I go to the hanger next I'll see if the light is controlled by the dynon but I have my doubts. I'm no EE but know how to measure Vdc.
 
rk2436 said:
It flies so nice anytime of the day works for me. When I go to the hanger next I'll see if the light is controlled by the dynon but I have my doubts. I'm no EE but know how to measure Vdc.
Click to expand...

The cockpit light intensity is controlled by the Dynon screen brightness control (unless you have a later version avionics kit that included a separate dimmer control mounted in the panel.
The screen controls a PWM circuit in the AV-50000 box.
A PWM circuit has a pulsed DC output which when measured with a DC volt meter will not indicate the actual full voltage, but the RMS value based on what the pulse width (duration of on time vs off time) is.
 
I have a D-180 and it also controls brightness with PWM negative voltage just like the SkyView.
 
Many DC voltmeters display the average voltage over time. If a 13 volt battery is repeatedly turned on for 0.38 second and off for 0.62 seconds, the average voltage displayed on a DC meter could be about 5 volts even though the actual voltage is 13. An expensive meter or an oscilloscope is required to accurately measure PWM DC.
 
The red light puts out a quite narrow beam. Initially, I did not think it was working.
Then I discovered the beam was pointing up out of the canopy. When carefully adjusted downward, it now lights up the trim and light switches nicely when night flying.
 
Thanks, Joe. new information for me - appreciate your input. I've only flown the aircraft a few times at night and have been happy with the red light. Quite adequate - enough to see the switches and that's all you need.

Jack
 
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